docs: def load_content(self, account_id, urls):
          """Prefetches one or more URLs to the CDN edge nodes.
  
          :param int account_id: the CDN account ID into which content should be
                                 preloaded.
          :param urls: a string or a list of strings representing the CDN URLs
                       that should be pre-loaded.
          :returns: true if all load requests were successfully submitted;
                    otherwise, returns the first error encountered.
          """
  
          if isinstance(urls, six.string_types):
              urls = [urls]
  
          for i in range(0, len(urls), MAX_URLS_PER_LOAD):
              result = self.account.loadContent(urls[i:i + MAX_URLS_PER_LOAD],
                                                id=account_id)
              if not result:
                  return result
  
          return True